Plot
On 6 August 1897, the merchant ship Demeter washes ashore in England. Among its wreckage, the police find the log kept by her captain, Eliot.
One month earlier, Demeter has made port in Varna, Bulgaria, to receive cargo bound for London. A shipment of multiple large, wooden crates is delivered to the dock by local Romanian workers. However, upon delivery of the cargo, they declare that they must leave the area before sundown, and one of the men pays the quartermaster Wojchek and another crewman, Olgaren, a large sum of money. He wishes Demeter a safe voyage, before departing with the others.
Clemens, a doctor and graduate of the University of Cambridge, overhears that Demeter is looking for additional crewmen. He volunteers, arguing that his medical skills and knowledge of astronomy would make him a valuable asset, but Wojchek rejects him and hires an older man instead. While helping to load one of the crates, the man is startled upon recognizing a dragon emblem on the container, and accidentally releases the tackle rope, causing the crate to fall; Clemens witnesses the accident and saves Eliot's grandson, Toby, from being crushed by the loose crate. The newly hired man declares the dragon emblem a "bad omen" and leaves; out of gratitude for his intervention, Eliot hires Clemens as a replacement. Clemens meets the rest of the crew: Joseph, Petrofsky, Larsen, and Abrams.
After the ship leaves port, another crate falls and breaks open in the cargo hold. Clemens finds a woman inside, buried in soil, and performs blood transfusions to treat (what he believes to be) an infection. Later, in the Aegean Sea, Clemens and Olgaren see a mysterious figure shrouded in fog on the deck.
The following night, all the animals aboard the ship are found dead, including the ship's dog. The crew, fearing a rabies outbreak, throws the carcasses overboard. While on night watch, Petrofsky is attacked and killed by a humanoid creature. Anna, the woman in the crate, awakens the next day and warns the crew about a "monster" from Transylvania, a creature that feeds on the blood of humans. She explains that the people of her village call him Dracula, and that she was given to him as a "slave of blood" so that he would leave the village in peace. She warns Clemens that Dracula is aboard the ship and needs to feed, revealing several bite marks on her body.
Dracula kills Larsen and bites Olgaren, turning him into a vampiric thrall. Olgaren is temporarily restrained, but breaks free and begins hunting Toby, trapping him in the captain's quarters with Dracula. As the crew attempts to save him, Toby is bitten by Dracula. The next morning, the vampiric Olgaren, who had been tied to the mast by the crew, bursts into flames as the rising sun touches his body. In the evening, Joseph knocks Abrams out and escapes on a lifeboat, but Dracula chases and kills him. Despite blood transfusions from his grandfather, Toby dies the following day, and is wrapped in parts of the sailcloth for his burial-at-sea. During the funeral, the captain believes he sees Toby moving; he unwraps him, only for Toby to suddenly attack. The vampiric Toby then immolates in the sunlight (and severely burns his grandfather) before Clemens is able to throw him into the ocean.
The remaining crew want to destroy the ship and drown Dracula to prevent him from causing chaos once they reach London. Abrams, Wojchek, and Eliot are all killed by Dracula, and Anna is bitten again during an attempt to save Clemens. Clemens rescues Anna by hitting Dracula with an axe, and Anna manages to crush Dracula with a part of the mast. Anna and Clemens jump ship, thinking the vampire is dead, but the ship ends up running aground on the British coast, enabling Dracula to push the mast off of his body and escape.
As Anna and Clemens float on debris, she reveals to him that she is now becoming a vampire after Dracula's bite; the blood transfusions only delayed the process. As the day dawns, not wanting to become a monster, Anna willingly self-immolates in the sunrise, as Clemens drifts ashore.
Arriving in London, Clemens goes to a local tavern, where he draws Anna's portrait in his notebook. He hears the knocking signal from the Demeter's crew of "all clear", and then sees Dracula, dressed as an aristocrat, laughing at him; the vampire disappears. Leaving the pub, Clemens sees Dracula's shadow and follows him; he vows, for the memory and honour of his dead companions, that he will kill Dracula and send him back to Hell.
